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71.
To enhance medical cooperation between the hospitals and clinics around Osaka local area, the healthcare network system, named Osaka Community Healthcare Information System (OCHIS), was established with support of a supplementary budget from the Japanese government in fiscal year 2002. Although the system has been based on healthcare public key infrastructure (PKI), there remain security issues to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority in contract with the Japanese Medical Information Systems Organization (MEDIS) in 2003. This paper describes the experimental design and the results of the study concerning message security.  相似文献   
72.
目的:探讨胺碘酮对大鼠睾丸质量、形态、酶活性及精子活力的影响.方法:健康雄性SD大鼠随机分为对照组、低剂量组和高剂量组,连续灌胃方式给予胺碘酮4周.处死大鼠后,分离大鼠双侧睾丸,并称重;光学显微镜观察精子活力,H-E染色观察睾丸形态;采用乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)、一氧化氮合酶(NOS)及一氧化氮(N...  相似文献   
73.
Artemisinin, isolated from the Chinese plant Artemisia annua, has been used for many years to treat different forms of malarial parasites. In this study, we explored the anti-inflammatory activity of artemisinin and the underlying mechanism of this action. We demonstrated that the anti-inflammatory effects of artemisinin in TPA-induced skin inflammation in mice. Then the artemisinin significantly inhibited the expression of NF-κB reporter gene induced by TNF-α in a dose-dependent manner. Artemisinin also inhibited TNF-α induced phosphorylation and degradation of IκBα, p65 nuclear translocation. Artemisinin also has an impact on upstream signaling of IKK through the inhibition of expression of adaptor proteins, TNF receptor-associated factor 2 (TRAF2) and receptor interacting protein 1 (RIP1). Furthermore, pretreatment of cells with artemisinin prevented the TNF-α-induced expression of NF-κB target genes, such as anti-apoptosis (c-IAP1, Bcl-2, and FLIP), proliferation (COX-2, cyclinD1), invasion (MMP-9), angiogenesis (VEGF), and major inflammatory cytokines (TNF-α, iNOS, and MCP1). We also proved that artemisinin potentiated TNF-α-induced apoptosis. Moreover, artemisinin significantly impaired the ROS production and phosphorylation of p38 and ERK, but did not affect the phosphorylation of JNK. Taken together, artemisinin may be a potentially useful therapeutic agent for inflammatory-related diseases.  相似文献   
74.
Aconitine is a well-known arrhythmogenic toxin and induces triggered activities through cardiac voltage-gated Na+ channels. However, the effects of aconitine on intracellular Ca2+ signals were previously unknown. We investigated the effects of aconitine on intracellular Ca2+ signals in rat ventricular myocytes and explored the possible mechanism of arrhythmogenic toxicity induced by aconitine. Ca2+ signals were evaluated by measuring L-type Ca2+ currents, caffeine-induced Ca2+ release and the expression of NCX and SERCA2a. Action potential and triggered activities were recorded by whole-cell patch-clamp techniques. In rat ventricular myocytes, the action potential duration was significantly prolonged by 1 µM aconitine. At higher concentrations (5 µM and 10 µM), aconitine induced triggered activities and delayed after-depolarizations (6 of 8 cases), which were inhibited by verapamil. Aconitine (1 µM) significantly increased the ICa-L density from 12.77 ± 3.12 pA/pF to 18.98 ± 3.89 pA/pF (n=10, p<0.01). The activation curve was shifted towards more negative potential, while the inactivation curve was shifted towards more positive potential by 1 μM aconitine. The level of Ca2+ release induced by 10 mM caffeine was markedly increased. Aconitine (1 µM) increased the expression of NCX, while SERCA2a expression was reduced. In conclusion, aconitine increased the cytosolic [Ca2+]i by accelerating ICa-L and changing the expression of NCX and SERCA2a. Then, the elevation of cytosolic [Ca2+]i induced triggered activities and delayed after-depolarizations. Arrhythmogenesis toxicity of aconitine is related to intracellular Ca2+ signals.  相似文献   
75.
目的:探讨亚硒酸钠对大鼠胃癌变前期胃窦粘膜G细胞、D细胞和EC细胞的影响。方法:用免疫组织化学及图像分析法,观察亚硒酸钠对N-甲基-N’-硝基-N-亚硝基胍诱发的大鼠胃癌变前期胃窦粘膜G细胞、D细胞和EC细胞的变化。结果:N-甲基-N’硝基-N-亚硝基胍短期灌胃后(阳性对照组),胃窦粘膜G、D、EC细胞的数量和平均光密度值(OD值)与正常对照组比较均显著减少(P〈0.01)。N-甲基-N’-硝基-  相似文献   
76.
本文报告采用髓鞘碱性蛋白 (MBP )的修饰性肽段配体 (APL )对多发性硬化症 (MS )患者治疗 1年后 ,在细胞克隆水平分析T细胞免疫应答的结果。从 5例患者外周血淋巴细胞中建立了 31个APL特异性T细胞系。首先测定患者和健康人体内APL特异性T细胞的反应频率 ,发现患者中平均为 31 6%± 2 3 7% ,而 10例对照者中仅为 5 %± 2 %。 31株APL反应性T细胞系对APL抗原表现出高度的增殖特异性。同时发现 ,APL特异性T细胞系与MBP优势肽段 (氨基酸 83 99)发生交叉反应的比例 ,患者中为 19 4% (6/ 31) ,而对照组中仅有 4 3% (1/ 2 3)。未发现与MBP优势肽段 83 99有交叉反应。来自MS治疗组的APL特异性T细胞系中 ,67%分泌IL 5和 /或IL 13,表明这些T细胞系具有Th2细胞特性。以上结果提示 ,这一修饰性MBP多肽作为一种治疗性疫苗 ,有可能在体内通过诱导Th2调节细胞 ,下调自身反应性T细胞介导的免疫损伤 ,发挥治疗作用。  相似文献   
77.
PURPOSE: The extent of the hemodynamic and metabolic impairments in adult patients with moyamoya disease is still controversial. The aim of the present study was to evaluate the hemodynamic and metabolic status in relation to the development of basal moyamoya vessels (BMVs). METHODS: The cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO2), oxygen extraction fraction (OEF), and cerebral blood volume (CBV) were measured using PET in ten patients with ischemic adult moyamoya disease (mean age, 36.6 years) and six age-matched normal controls (mean age, 33.3 years). The cerebrovascular reserve (CVR) after acetazolamide (ACZ) loading was also estimated using iodine-123 N-isopropyl-p-iodo amphetamine single photon emission computed tomography (123I-IMP SPECT). RESULTS: Based on the angiographic findings, eleven cerebral hemispheres with well-developed BMV (extensive BMV hemispheres) and nine cerebral hemispheres with diminished BMV (diminished BMV hemispheres) were identified. The main routes of collateral circulation in extensive BMV hemispheres were BMVs and leptomeningeal anastomoses. On the other hand, in diminished BMV hemispheres, transdural anastomosis was predominant, and leptomeningeal anastomoses were less developed. In cortices distal to the occluded internal carotid artery, the extensive BMV hemispheres exhibited a significantly lower CBF, CMRO2, CBF/CBV, and CVR (p < 0.05) and a significantly higher CBV and OEF than in diminished BMV hemispheres and controls (p < 0.05). Except for the CBF in the white matter, the mean hemodynamic and metabolic parameters of the diminished BMV hemispheres were not significantly different from those of the controls. CONCLUSION: The extensive development of basal moyamoya vessels is a sign of severe hemodynamic impairment in adult patients with ischemic moyamoya disease. The results may not apply to adults with hemorrhagic onset.  相似文献   
78.
BackgroundThere is an increasing demand for prognostic immune biomarkers of cancer. The prognostic significance of immune markers has been shown for various cancers, but biomarkers of bladder cancer (BCa) have not been fully evaluated. To clarify the role of human leukocyte antigen DR alpha chain (HLA-DRA) in BCa development, we examined expression of HLA-DRA mRNA in tissue samples of non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC).Materials and MethodsTissues of 96 NMIBC, 43 MIBC and 59 controls comprising noncancerous BCa surrounding tissues were used to examine the expression of HLA-DRA gene by real-time polymerase chain reaction. The expression of up-stream genes regulating HLA-DRA were also measured to explain the role of HLA-DRA in BCa.ResultsPatients with high grade NMIBC showed higher expression of HLA-DRA than those with low grade NMIBC (P < 0.05). In addition, NMIBC patients who progressed to MIBC showed high expression of HLA-DRA mRNA. Kaplan-Meier analysis showed that NMIBC patients with low expression of HLA-DRA had better progression-free survival than those with high expression (P = 0.004). Moreover, the expression of genes regulating HLA-DRA varied in NMIBC and MIBC, indicating a different immunoregulation effect of HLA-DRA in both cancers.ConclusionsHigh expression of HLA-DRA in NMIBC patients has implications for patient stratification strategies, as well as for BCa tumor immunology.  相似文献   
79.
糖尿病雄性生殖损伤及其发生机制   总被引:3,自引:2,他引:3  
糖尿病是由多种病因引起的代谢性疾病 ,其生殖损伤严重危害机体的健康。本文综述了糖尿病雄性生殖损伤病理生理改变及其发生机制 ,高血糖导致的氧化应激在糖尿病雄性生殖损伤中的重要作用 ,以及某些抗氧化剂可能成为有效治疗糖尿病生殖损伤的药物。  相似文献   
80.
目的 研究多层(16层)螺旋CT(multi slice spiral CT,MSCT)冠状动脉造影成像在评价冠状动脉支架通畅性的临床意义,并分析影响其成像质量的因素.方法 采用MSCT对32例冠状动脉支架患者行冠状动脉成像检查,以多种方式重建显示冠状动脉支架的位置、形态、术后再狭窄等.其中7例经X线冠状动脉造影进一步证实.将CT冠状动脉图像质量分三级予以评价,分析其影响图像质量的因素.结果 MSCT显示所有32例患者41个冠状动脉支架的形态、位置,其中5个支架术后出现再狭窄;7例患者9个支架与冠状动脉造影对照,诊断符合率为88.9%;图像质量优良率为87.5%(28/32例),心率<60/min、61~70/min和>71次/min图像质量优良率分别占94.7%、88.9%和50.0%,三种不同心率对图像质量显示有显著性差异(χ2=16.354,P<0.01).结论 MSCT冠状动脉成像是一种较可靠的冠状动脉支架无创性评价方法,对支架开通性显示较好,但对支架内情况显示受限,图像质量受心率等因素影响,质量控制是关键.  相似文献   
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